1. Field
One or more example embodiments relate to an electrolyte for a lithium battery and a lithium battery including the electrode.
2. Description of the Related Art
Lithium secondary batteries that are used (utilized) in portable electronic devices (including PDA, mobile phones, and laptops) for information and communication, or in electric bicycles or electric vehicles have discharge voltages that are at least twice as large as that of conventional batteries. Accordingly, lithium secondary batteries may have high energy density.
A lithium secondary battery includes a cathode and an anode, each includes an active material capable of intercalation and deintercalation of lithium ions, and an organic electrolytic or a polymer electrolyte that is filled between the cathode and the anode. Here, oxidation and reduction reactions occur during intercalation/deintercalation of lithium ions in the cathode and the anode, thereby generating electric energy.
With the expanding use (usage) of lithium secondary batteries in the electric vehicles and power storage fields, electrode active materials for use (usage) at high voltages have become available. Use (usage) of a relatively low-potential anode active material and a relatively high-potential cathode active material has led to a narrower potential window of the electrolyte, so that the electrolyte becomes more likely to decompose on a surface of the cathode/anode. In addition, lithium secondary batteries for electric vehicles and power storage are likely to be exposed to external high-temperature environment conditions, and the temperatures of these lithium secondary batteries may rise during instantaneous charging and discharging. Accordingly, lifetime (lifespan) and stored energy quantity of the lithium secondary battery may be reduced in such high-temperature environment conditions.
Therefore, stability and cycle characteristics of the lithium battery at high voltages are important concerns for application of the lithium battery in the electric vehicle fields or the like.